Dry sour cream powders are on the market today, but they are mostly dried, natural, cultured cream to which amounts of other ingredients have been added. Such a sour cream powder is disclosed in Noznick et al U.S. Pat. No. 3,792,178. The patent describes the use of an amount of a sodium, ammonium or potassium phosphate as a protein peptizing agent mixed with cultured sour cream prior to spray drying, to produce a powder readily dispersible in water.
Conventionally, the taste and texture of such products are poor. The reason for this is that sour cream, as with other milk products, looses a lot in the spray drying process, due to the heat employed. Off-flavors are developed, and reconstitution with milk or water becomes difficult. Even with the addition of solubilizing ingredients, such as in the Noznick et al patent, and imitation or natural flavors, the off-flavors are difficult to mask, and the tendency to form a curdy mass makes it difficult to obtain a product having the body, texture, and consistency of natural sour cream.
In a Bangert et al U.S. Pat. No. 3,560,220, it is suggested that some of these difficulties can be overcome by using, as a base, a spray-dried component containing about 40% fat (76.degree. coconut oil), about 12% sodium caseinate, and about 35% acid whey solids.
Also included in the spray-dried component is an emulsifier such as propylene glycol monostearate, and a gum such as carboxymethylcellulose. The spray-dried component is dry blended with citric acid, aluminum potassium sulfate, sodium carrageenan, flavor and colorants. The mix is said to be reconstitutable with milk, and when so reconstituted, is said to have a smooth texture, absence of curdling, and tanginess.
It would appear that a primary objective of this patent is utilization of acid whey, a by-product of cottage cheese. Acid whey contains a very high percentage of lactose, and accordingly is very bitter. At a 35% level, this bitterness also would be difficult to mask. Further, the sodium caseinate is employed at a very high level (12%), and it's flavor would be difficult to mask.
A Petrowski et al U.S. Pat. No. 4,045,589 describes a dry coffee whitener which is protein free and contains a chemically modified dextrinized starch having a lipophillic character. The whitener also contains a fat or oil, and an emulsifier to stabilize the emulsion upon reconstitution in coffee. A buffering agent is mixed with the dried emulsion to improve taste. It is indicated near the end of the specification for the patent that the coffee whitener product "may be used in preparing dried imitation sour cream mix, dried chip dip mix, dried creamy salad dressing mix, and the like. In such products, where an acidic taste is not objectionable, buffering salts need not be dry blended with the dried emulsion concentrate."
The patent gives no listing of other ingredients which may be used in preparing a dried imitation sour cream mix, nor proportions, nor characteristics of the end product. It is not indicated in the patent that such sour cream mix would have utility as a base in food recipes where natural sour cream is conventionally employed. In the present invention, the presence of a protein, in a coffee whitener-type formulation, was found to be critical.
A major problem in making tart tasting products from an acid containing dry mix, by reconstitution with milk, is that the pH of the milk is lowered below the isoelectric point of the milk protein causing curdling. This problem is alluded to in an Eskritt et al U.S. Pat. No. 3,955,009, which proposes that with the use of pregelatinized starch and a hydrocoloid gum, the curdling can be avoided. It is indicated that the pregelatinized starch permits such rapid rehydration and quick setting that the coagulation and curdling of the milk proteins is prevented. The patent is not concerned with the preparation of an imitation sour cream. The principle ingredients in the dry mix are sucrose, pregelatinized starch, citric acid, emulsifier and guar gum. No coffee whitener-type ingredient is used in the Eskritt et al formulation.
Other patents dealing with reconstitution of acid containing dry mixes with milk include Gardiner U.S. Pat. No. 3,917,875; Igoe U.S. Pat. Nos. 3,996,390, 4,058,636 and 4,169,854; Haber U.S. Pat. Nos. 4,081,566 and 4,081,567; and Sirett et al U.S. Pat. No. 4,264,638.
Prior art patents which deal with the preparation of imitation sour creams include Loter U.S. Pat. Nos. 3,355,298 and 3,437,494; Little U.S. Pat. Nos. 3,370,955, 3,359,116, and 3,391,002; Edwards U.S. Pat. No. 3,432,306, and Tatter et al U.S. Pat. No. 3,433,643. These are not dry blends.
The Ellinger U.S. Pat. No. 3,563,761 describes an imitation sour cream containing sodium caseinate, vegetable shortening, corn syrup solids, stabilizers, emulsifiers, and water to bring the composition to 100%. The patent does not describe a dry blend suitable for reconstitution with milk.
No prior patent of which applicant is aware teaches or suggests the use of a casein-containing coffee whitener formulation as a base for the preparation of an imitation, non-dairy sour cream, which is suitable for multiple uses, including sour cream containing food recipes; nor a sour cream dry mix containing the same (a coffee whitener formulation), and acid, reconstitutable with milk.